In recent years, vehicles such as cars, are provided with an image processing system that functions both as a sensing camera for acquiring information on around the vehicle and as a raindrop detection camera for detecting a raindrop attached to a windshield of the vehicle (for example, see Patent Literature 1: Japanese Patent No. 4326999). Such an image processing system is used in, for example, a system for automatically removing raindrops attached to a windshield of a vehicle by a windshield wiper.
Patent Literature 1 discloses an image processing system that includes an image processing apparatus, a light source, and an optical filter so as to function both as a sensing camera and a raindrop detection camera, and that captures images of raindrops on the outer surface of the windshield by applying light from the light source. In the image processing system, a bandpass filter for detecting a raindrop is provided in a part of the optical filter. In general, it is difficult to change the exposure amount in only a part of a captured image. Therefore, the light emission intensity of the light source is changed so that, while exposure is adjusted to a portion where the bandpass filter is not provided and where affected by external light, the same exposure value can be obtained in a portion where the bandpass filter is provided.
However, the amount of light incident on the camera from the outside of the vehicle greatly varies between, for example, day, and night or depending on weather. The variation is extremely large, ranging from 0.1 lux to a hundred thousand lux. In the image processing system described above, it is necessary to increase the light emission intensity of the light source in proportion to the external light. Therefore, there are problems in terms of power consumption and in terms of safety affected by intensive light emitted to the outside of the vehicle.
Furthermore, readiness is important in detecting other vehicles or white lines. Therefore, it is important to maintain a high frame rate for frames to be captured for sensing.
The present invention has been made to solve the above problems in the conventional technologies, and it is an object of the present invention to provide an image processing system that can, in a system in which one imaging device detects both a foreign matter and information on around the vehicle, reduce the power consumption, enhance the safety, and prevent a reduction in the frame rate for sensing due to insertion of frames for detecting a foreign matter, and to provide a vehicle including the image processing system, an image processing method, and a computer program product.